Neuropsychological testing can play a major role in the diagnosis of dementia by documenting cognitive deficits, the key criteria for the diagnosis. Because the most common dementia diagnosis, Alzheimer's disease, focuses on memory impairment, tests to assess this domain and to detect and characterize memory deficit are well established with recognized predictive value. Other neuropsychological domains are less well characterized and there are fewer tools to assess them. One domain that has been characterized as important in a number of other dementias is executive function. Improved neuropsychological assessment and characterization of other domains, such as executive function and attention, may assist in better identifying the pathophysiology of deficits in these areas, perhaps in combination with new technologies such as functional imaging. Finally, improved assessment tools for specific cognitive domains should assist in identifying a broad range of cognitive deficits at earlier stages and ultimately lead to more effective interventions for a wider range of cognitive deficits.